1. Field of the Invention
This invention generally relates to disc brakes for bicycles. More specifically, the present invention relates to a disc brake caliper with a single piston unit that is used with a disc brake rotor having a pair of floating disc members.
2. Background Information
Bicycling is becoming an increasingly popular form of recreation as well as a means of transportation. Moreover, bicycling has become a very popular competitive sport. Whether the bicycle is used for recreation, transportation or competition, the bicycle industry is constantly improving their components. One particular component of the bicycle, which has been extensively redesigned over the past years, is the braking systems of bicycles. In particular, the braking power of the braking systems is constantly being increased.
There are several types of bicycle brake devices, which are currently available on the market. Examples of some types of common bicycle brake devices include rim brakes, caliper brakes and disc brakes. If a rider wants a very high performance brake system, then the rider typically wants a disc brake system. Disc brake systems provide a substantial braking power in relationship to the amount of braking force applied to the brake lever. Moreover, disc brake systems typically provide a high level of consistency in all types of weather and riding conditions. Of course, riders constantly desire better performance from disc braking systems, i.e., disc brake systems that have more braking power.
Accordingly, brake systems have been developed with two disc rotors. Typically, the double disc brake systems utilize a fixed middle friction member and a pair of end friction members that move towards the middle friction member. However, one drawback to this type of braking system is that it is expensive because it requires a pair of pistons to move the end friction members towards the middle. Moreover, a caliper with a pair of piston units is also substantially heavier than a caliper housing with a single piston unit. Another problem with prior double disc braking systems is that the caliper housing must be correctly aligned with the disc members of the rotor to avoid bending of the disc members.
In view of the above, there exists a need for a disc brake, which overcomes the problems of prior art disc brakes. This invention addresses this need in the prior art as well as other needs, which will become apparent to those skilled in the art from this disclosure.
One object of the present invention is to provide a bicycle disc brake assembly with a double disc rotor for increased braking power.
Another object of the present invention is to provide a disc brake assembly that is relatively compact and lightweight in relation to the amount of braking power.
Another object of the present invention is to provide a disc brake assembly that is relatively inexpensive to manufacture.
The foregoing objects can be basically attained by providing a disc brake rotor comprising a support member, a first disc brake member and a second disc brake member. The support member has an outer attachment portion and an inner attachment portion configured to be coupled to rotate with a rotating member about a center rotational axis. The first disc brake member is movably coupled to the outer attachment portion for a first amount of axial movement relative to the support member. The second disc brake member is movably coupled to the outer attachment portion for a second amount of axial movement relative to the support member. The second amount of axial movement is different from the first amount of axial movement. The second disc brake member is axially spaced from and arranged substantially parallel to the first disc brake member.
The foregoing objects can be basically attained by providing a disc brake assembly comprising a support member, a first disc brake member, a second disc brake member, a caliper housing, a first end friction member, a second end friction member and a middle friction member. The support member has an outer attachment portion and an inner attachment portion configured to be coupled to rotate with a rotating member about a center rotational axis. The first disc brake member is movably coupled to the outer attachment portion for a first amount of axial movement relative to the support member. The second disc brake member is movably coupled to the outer attachment portion for a second amount of axial movement relative to the support member. The second amount of axial movement is different from the first amount of axial movement. The second disc brake member is axially spaced from and arranged substantially parallel to the first disc brake member. The caliper housing has a piston unit movably coupled thereto between a release position and a braking position for applying a braking force to the first and second disc brake members. The first end friction member is movably coupled to the housing by the piston unit to move between the release position and the braking position. The second end friction member is coupled to the housing and arranged substantially parallel to the first end friction member. The middle friction member is movably coupled to the housing between the first and second end friction members.
These and other objects, features, aspects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the present invention.